This invention relates to improvements in the installation and joining of end-to-end track sections of industrial conveyor systems employing track sections of low tolerance construction and, in particular, to a modular track configuration employing end connections which ensure proper alignment of the running surfaces of the end-to-end sections.
Conventional power and free conveyor systems utilize a track formed by end-to-end straight, curved, dip and special track sections that are typically joined by flange couplings at their abutting ends which must be welded together to form a permanent joint. In an overhead power and free conveyor, for example, the power track is provided by a steel I-beam mounted above and coextensive with a pair of opposed channel iron members. The I-beam, often referred to as the power rail, supports the drive trolleys and drive chain with the opposed channel members forming a track which supports the free trolleys and associated load-bearing carrier assemblies. In a typical installation these track sections are suspended from overlying main beams of the superstructure of the building in which the conveyor is installed as, for example, disclosed in U.S. Pat. No. 4,635,558.
Both the I-beams and the channel members providing the power track and the free track, respectively, are formed from hot rolled steel with manufacturing tolerances on the order of .+-.1/8 inch. Accordingly, it is often difficult to precisely align the running surfaces of the track sections at a joint and, once alignment is achieved, hold the sections in proper alignment. As a result, the conventional installation technique employs coupling flanges at the joints which are initially bolted together to hold the track members once they are aligned, followed by welding the coupling flanges together to preclude movement (and attendant misalignment) that could otherwise occur due to vibration of the tracks during operation of the conveyor system. Therefore, installation heretofore has been very labor intensive due to the need to adjust for misalignment caused by wide manufacturing tolerances and the expense of welding the bolted flanges at the track joints.